[RM57Lx LaunchPad / HDK] Get data from IMU (MPU 9250) 9-axis

honig

Dear community,

I'd like to get data from a position / angular sensor : IMU (MPU 9250) 9-axis

I can use UART by connecting VCC/GND/TX/RX. It should not be difficult. However I found several posts in Arduino forum which show how to use IMU with I2C communication protocol. Which protocol is more recommended in this case with TI RM57Lx LaunchPad / HDK?

over 10 years ago

0 Martin Valencia over 10 years ago

Guru 15175 points

the MPU 9250 module also has a SPI communication?

0 honig over 10 years ago in reply to Martin Valencia

Intellectual 745 points

Hi Martin,

Unfortunately, this product does not provide SPI communication protocol. Why SPI? Is it much faster than UART and I2C?

0 Anthony F. Seely over 10 years ago in reply to honig

TI__Guru 69050 points

Honig,

I think Martin's SPI idea is right if this is the chip on the board: www.digikey.com/.../4626450

The SPI spec for that chip is 20MHz clock, which is 40x faster than I2C and more than 40x faster than UART. Since there are 9 sensors on that chip maybe it makes sense to look at whether you can 'hack' the board to bring the SPI interface out to pins.

If not maybe design a booster pack with this chip and SPI and share w. the launchpad community?
www.ti.com/.../byob.html

there are some people who can help you if you have interest in this.

0 Martin Valencia over 10 years ago in reply to Anthony F. Seely

Guru 15175 points

hehehehe!, honig You can count on me, as someone interested!

it is true what says Anthony, by the amount of data to be transmitted would be perfect if you can work through the SPI, while UART is too slow and I2C may present some problems of compatibility with the Hercules.
The SPI protocol would be perfect for the amount of information to be transmitted and data rate.

0 honig over 10 years ago in reply to Anthony F. Seely

Intellectual 745 points

Hi Anthony,

Thank you for the detailed explanation!

0 honig over 10 years ago in reply to Martin Valencia

Intellectual 745 points

Hi Martin,

> I2C may present some problems of compatibility with the Hercules
In which cases, should I2C be avoided in Hercules? Some other modules in Hercules may have conflicts with I2C? For example, several sensors communicate with Hercules at the same time?

0 Martin Valencia over 10 years ago in reply to honig

Guru 15175 points

No, it is necessary to avoid using the I2C module with the Hercules family, the problem is that it is difficult to work with this.
I still have not succeeded in doing work well, so I recommend SPI and serial communication.

there inverter modules with SPI and I2C communication, so it is better to know both protocols.

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[RM57Lx LaunchPad / HDK] Get data from IMU (MPU 9250) 9-axis